Modern gas turbine engines generally must operate under strict emissions guidelines, particularly with respect to nitrogen oxides (NOx). As such, gas turbine engine design must operate at high efficiency without producing undesirable air emissions. Many modern gas turbine engines thus use a very lean, premixed flame for low NOx combustion.
One way to limit turbine emissions is to ensure good mixing of the fuel and the air in the combustor. Proper mixing may involve mixing flow manipulation using dilution tuning or similar methods. Tuning a combustor in the field, however, may be difficult and time consuming. Moreover, the need to tune properly a combustor also may influence the time required for initial commissioning and/or cause other types of delays.
There is thus a desire for an improved combustor and other types of turbine components that promote good mixing of both fuel and air while providing high overall efficiency with limited emissions. Preferably the combustor or the other components may be used with new and existing equipment.